Biological significance of oligosaccharides is growing rapidly and necessitates development of efficient methods of their synthesis. Enzymatic glycosylations, in comparison with the chemical methods, are especially useful in the glycosylation of complex biologically active substances, where drastic conditions or the use of toxic (heavy) metal catalysts are generally undesirable. A key advantage of enzymatic methods is their stereo- and regioselectivity. Two types of enzymes can be used to obtain oligosaccharides: hydrolytic enzymes, which catalyze thermodynamically controlled hydrolysis or kinetically controlled transglycosylation and transferases. In this paper, preparation of oligosaccharides using reverse glycosylation is summarized.